1. Field of the Invention
The present invention relates to a light emitting diode (LED) driving chip, an LED driving system and an associated method, and more particularly, to an LED driving chip having eight pins, an LED driving chip having six pins, an LED driving system and an associated method.
2. Description of the Prior Art
Regarding the existing LED driving chip, it requires an alternating current to direct current (AC/DC) power circuit and a direct current to direct current (DC/DC) power circuit to operate normally. However, the overall power efficiency of such a two-stage power circuit is not high enough due to the fact that the power efficiency of the AC/DC power circuit is different from that of the DC/DC power circuit. When the AC/DC power circuit and the DC/DC power circuit are both used, the overall power efficiency equals the product of the power efficiency of the AC/DC power circuit and the power efficiency of the DC/DC power circuit, thus resulting in power efficiency degradation of an LED driving system.
Further, when a conventional LED driving chip is designed to drive four LED strings, the conventional LED driving chip has at least 16 pins; and when the conventional LED driving chip is designed to drive one LED string only, the conventional LED driving chip has at least 8 pins. Hence, another issue encountered by the conventional LED driving chip is high packaging cost. Moreover, a larger pin count makes an LED driving chip occupy a larger area. Hence, how to integrate pins of an LED driving chip so as to reduce the pin count of the LED driving chip and raise the power efficiency thereof has become an important issue to be solved.